RE: [PATCH v2 2/3] usb: chipidea: imx: support disabling runtime-pm

[Jun Li]

> -----Original Message-----
> From: Francesco Dolcini <francesco@xxxxxxxxxx>
> Sent: Friday, May 5, 2023 7:00 PM
> To: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>; Jun Li <jun.li@xxxxxxx>
> Cc: Francesco Dolcini <francesco@xxxxxxxxxx>; devicetree@xxxxxxxxxxxxxxx;
> festevam@xxxxxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx;
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>;
> linux-kernel@xxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx;
> peter.chen@xxxxxxx; robh+dt@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx;
> shawnguo@xxxxxxxxxx; Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>;
> Francesco Dolcini <francesco.dolcini@xxxxxxxxxxx>
> Subject: Re: [PATCH v2 2/3] usb: chipidea: imx: support disabling runtime-pm
> 
> On Fri, May 05, 2023 at 12:06:18PM +0200, Luca Ceresoli wrote:
> > On Fri, 5 May 2023 09:49:16 +0000
> > Jun Li <jun.li@xxxxxxx> wrote:
> > > Is your board design similar like Francesco's as below?
> >
> > Possibly, but I'm afraid I can't say: I am using the Toradex Colibri
> > i.MX6ULL SoM, whose schematics are not public.
> 
> I can confirm that it's the same.

Thanks Francesco for the confirmation, had a check with design team,
there is no status bit which can be used to judge the VDD_USB_CAP is
powered or not, so we have to add a board level dts property to tell
this usb phy driver to bypass MXS_PHY_DISCONNECT_LINE_WITHOUT_VBUS.

Before send a formal patch, I want to confirm this should work for your
HW design, like below simple hack:

diff --git a/drivers/usb/phy/phy-mxs-usb.c b/drivers/usb/phy/phy-mxs-usb.c
index e1a2b2ea098b..ec5ee790455e 100644
--- a/drivers/usb/phy/phy-mxs-usb.c
+++ b/drivers/usb/phy/phy-mxs-usb.c
@@ -178,7 +178,6 @@ static const struct mxs_phy_data imx6sx_phy_data = {
 };
 
 static const struct mxs_phy_data imx6ul_phy_data = {
-       .flags = MXS_PHY_DISCONNECT_LINE_WITHOUT_VBUS,
 };
 
 static const struct mxs_phy_data imx7ulp_phy_data = {

Thanks
Li Jun

> 
> Francesco